References

^Klein Goldewijk, K. , A. Beusen, M. de Vos and G. van Drecht (2011). The HYDE 3.1 spatially explicit database of human induced land use change over the past 12,000 years, Global Ecology and Biogeography20(1): 73-86. doi:10.1111/j.1466-8238.2010.00587.x (pbl.nl).
Goldewijk et al. (2011) estimate 188 million as of AD 1, citing a literature range of 170 million (low) to 300 million (high).
Out of the estimated 188 million, 116 million are estimated for Asia (East Asia, South Asia, Southeast Asia, and Central Asia, excluding Western Asia),
44 million for Europe and the Near East, 15 million for Africa (including Roman Egypt and Roman North Africa), 12 million for Mesoamerica and South America. North America and Oceania were at or below one million.
For AD 1000, they estimate the world population at 295 million .
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